UW Study Determines Wyoming Wind Could Benefit Colorado Economically

April 3, 2013

Wyoming wind power could benefit the Colorado electric grid
both economically and environmentally, according to a study headed by a
University of Wyoming professor.

The report, titled “Wind Diversity Enhancement of
Wyoming/Colorado Wind Energy Projects,” focuses on the importance of diversity
in wind resources produced by Wyoming and Colorado, and the economic benefits
the combination of these complementary wind sources could potentially provide,
says Jonathan Naughton, a UW Department
of Mechanical Engineering professor and director of the Wind Energy Research Center.

“I think many people had the idea that wind diversity would
have an economic impact, but we had to put some numbers on it,” Naughton says.
“I think that’s what this report did.”

Wind diversity essentially means wind speeds at two
locations vary differently, Naughton says. Wind that blows at a high speed at
one location while it blows at a low rate of speed at another, and vice versa,
would be considered diverse sources of wind.

Making power created by wind less variable, or more
consistent over time, would create a more even and reliable flow of power to
communities using this energy source as well as improve the correlation of
wind energy availability to the actual customer demand for electricity,
Naughton says.

Plains winds in Colorado and the mountain-driven winds in Wyoming
are largely uncorrelated due to the physical processes responsible for the winds
at the different locations.

Wyoming’s wind blows harder than Colorado wind, and blows primarily
during the day, which is the highest energy demand or peak period for Colorado energy
consumers, according to the study. Wyoming wind can mitigate the ramping events
associated with the variable renewable energy sources on the Colorado energy
grid.

“The analysis shows that combining diverse renewable
resources from Wyoming with those in Colorado would result in mitigating the
amount of dispatchable generation required to address the variability of wind
and solar,” Wyoming Infrastructure Authority (WIA) board member J.M. Shafer
says in an April 2 WIA press release.

The report was commissioned by the WIA, which is based in
Cheyenne. Created by the Wyoming Legislature in 2004, the WIA’s mission is to
diversify and expand the state’s economy through improvements in Wyoming’s
electric transmission infrastructure to facilitate the consumption of Wyoming
energy in the form of wind, natural gas, coal and nuclear power, where
applicable.

Naughton co-wrote the report with Thomas Parish, a UW Department of Atmospheric Science
professor, and Jared Baker, a UW graduate student majoring in mechanical
engineering. A U.S. Department of Energy grant funded a major portion of the
study.

The study used one year of data, predicted by a weather
forecasting model, for multiple sites in Wyoming and Colorado. Computer
analyses were compiled from sites near Rawlins, Casper, Medicine Bow, the Southern
Laramie Valley and the Wheatland/Chugwater region in southeastern Wyoming.
Colorado sites included locations of existing wind farms at Cedar Creek, Peetz
Table, Cedar Point, Kit Carson and Colorado Green.

A savings in the tens of millions of dollars annually would
result from reduced payments for make-up power when Wyoming and Colorado
resources are combined. Assuming the make-up power is derived from fossil
fuels, reduction in greenhouse gases can be realized, Naughton says.

“It’s easier to integrate wind power into the grid,” he
says. “It saves money you don’t have to use for backup power that would likely
come from gas turbine engines fired by natural gas.”

For Wyoming’s wind resources to benefit Colorado, new
transmission infrastructure would be required. According to the WIA press
release, a transmission project -- the Wyoming-Colorado Intertie Project – that
originates in Wyoming is in development. The 345 kilovolt AC line would
originate in the Wheatland/Chugwater area and include an interconnection into
the Colorado grid in Morgan County, which is located in northeast Colorado.
That project, expected to be complete during 2017, is a public/private
partnership between LS Power Group and the WIA.

A National Renewable Energy Laboratory (NREL) study, also commissioned by the WIA, was
released the same day. The NREL study identified economic impacts relative to
transmission and generation infrastructure across state lines.

During the three-year construction period, about 4,000 jobs
-- 1,300 in Wyoming and 2,700 in Colorado -- would be generated annually.
Annual wages would range from $52,000-$75,000 for the construction jobs. About 300
permanent jobs in Wyoming and another 100 in Colorado -- with wages between
$41,000 and $63,000 -- would result, according to the study.

The UW wind study report was released to the WIA this week.
It is the second in a series of four that compares the geographic diversity of
Wyoming wind with wind resources in California, Colorado and Nebraska, and
within Wyoming, Naughton says.

The report will be formally presented at the WIA’s spring
board meeting at the Little America Hotel and Resort in Cheyenne May 15-16. The
meeting is open to the public. For more information, visit http://wyia.org or contact holly.martinez@wyo.gov.

Photo:These turbines are part of a wind farm near Medicine Bow.
The site was one of five in Wyoming where data was gathered for the UW study.
(Leann Naughton Photo)